Machine Design Multiple Choice Questions on “Bearings”.
1. Which of the following are functions of bearings?
a) Ensure free rotation of shaft with minimum friction
b) Holding shaft in a correct position
c) Transmit the force of the shaft to the frame
d) All of the listed
Answer: d
Clarification: Bearings are used for all the above listed purposes.
2. A radial bearing supports the load that acts along the axis of the shaft.
a) True
b) False
Answer: b
Clarification: Radial bearing supports the load acting perpendicular to the axis of the shaft.
3. A_______ bearing supports the load acting along the axis of the shaft.
a) Thrust
b) Radial
c) Longitudinal
d) Transversal
Answer: a
Clarification: Thrust bearing supports load acting along axis of shaft.
4. Sliding contact bearings, also called plain bearings have no problem of wear.
a) True
b) False
Answer: b
Clarification: Surface of shaft slide over surface of the bush resulting in friction and wear.
5. In steam and gas turbines, rolling contact bearings are used.
a) True
b) False
Answer: b
Clarification: Sliding contact bearings are generally used.
6. Which of the following are true about plasticity?
a) Permanent Deformation
b) Ability to retain deformation under load or after removal of load
c) Plastic deformation is greater than elastic deformation
d) All of the mentioned
Answer: d
Clarification: This is the basic definition of plasticity.
7. Which of the following is measure of stiffness?
a) Modulus of elasticity
b) Modulus of plasticity
c) Resilience
d) Toughness
Answer: a
Clarification: Stiffness is the ability of material to resist deformation under external load. Hence it is measured by modulus of elasticity.
8. Which of the following facts are true for resilience?
a) Ability of material to absorb energy when deformed elastically
b) Ability to retain deformation under the application of load or after removal of load
c) Ability of material to absorb energy when deformed plastically
d) None of the mentioned
Answer: a
Clarification: Toughness is ability to store energy till proportional limit during deformation and to release this energy when unloaded.
9. Modulus of resilience is defined as
a) Strain energy per unit volume
b) Strain energy per unit area
c) Independent of strain energy
d) None of the mentioned
Answer: a
Clarification: Modulus of resilience is strain energy per unit volume.
10. In gear boxes and small size motors, rolling contact bearings are used.
a) True
b) False
Answer: a
Clarification: In small size applications, rolling contact bearings are preferred.